Most of common eyeglass structures use screws to assemble the temples with the frame. However, the combination of screws is troublesome, which not only consumes materials but also increases assembly time. Therefore, it is quite inconvenient for manufacture and assembly. There is a structure that uses engaging studs and engaging holes to mate with each other, such that the frame and the temples can be assembled without using screws. However, for the glasses structure without screws, when in use, the front ends of the temples abut against the two sides of the frame to main the angles of the temples when unfolded. When the temples are unfolded beyond the limit, the engaging studs of the temples may disengage from the engaging holes of the frame to lose the pivot fixing function.
Taiwan Utility Model No. M259179 entitled “glasses capable of mounting temples stably” published on Mar. 11, 2005 is disclosed, comprising a lens unit and temples which are pivotally connected to two pivot portions of the lens unit. When the temples are unfolded, the frame and the lens unit abut against each other by corresponding abutting surfaces. The pivot portion is provided with two spaced stop blocks at upper and lower ends thereof. Each stop block has a stop groove with an opening facing rearward and a stop surface. Each temple has two support shafts to be inserted into the pivot holes of the lens unit and contact surfaces to be in contact with the stop surfaces of the stop blocks of the frame when the temple is unfolded. Through the engagement of the two abutting surfaces as well as the engagement of the contact surface and the stop surface, the temples can be assembled stably.
In the aforesaid patent, the pivot portions further have two upper and lower spaced grooves. The grooves extend to the corresponding stop grooves. Each temple has two upper and lower spaced protruding shafts horizontally extending towards the lens unit, a first stopper extending from the lower protruding shaft, and a second stopper extending from the upper protruding shaft. The first stopper has a first contact surface, and the second stopper has a second contact surface corresponding to the first contact surface. The first stopper and the second stopper are inserted into the corresponding stop grooves, respectively. The first stopper and the second stopper abut against extension pieces respectively, thereby preventing the support shafts from disengaging from the pivot holes due to torsion.
The aforesaid patent has the mechanism to prevent the support shafts from disengaging from the pivot holes. However, the first stopper and the second stopper are disposed at the forefronts of the protruding shafts, respectively. This not only influences the overall appearance and is complicated for manufacture. In particular, after the temples are unfolded many times, the first stopper and the second stopper may be damaged because of the excessive force of unfolding the temples. In general, the eyeglass lenses are performed with a coating surface treatment in order to increase the degree of the surface hardening of the lenses, thereby providing a wear-resistant effect. In the aforesaid patent, after the lens unit is immersed in the coating solution, the interior of the stop groove of the lens unit is a closed structure so that the coating solution is adsorbed to the stop groove due to vacuum suction. As a result, after the coating process is completed and the lens unit is heated and dried, the stop groove may be clogged with the dried coating, so the first stopper and the second stopper cannot be inserted into the stop grooves. It is not perfect for use. Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve these problems.